ole_type

tobj = WIN32OLE_TYPE.new('Microsoft Excel 9.0 Object Library', 'XlSheetType')
variables = tobj.variables
variables.each do |variable|
  puts "#{variable.ole_type} #{variable.name}"
end

The result of above script is following:
  INT xlChart
  INT xlDialogSheet
  INT xlExcel4IntlMacroSheet
  INT xlExcel4MacroSheet
  INT xlWorksheet